The 515 GN01 application measures the volume, mass and gross heat content of a Natural Gas. The flow computer uses a frequency volume flow input and analog temperature and pressure sensor inputs.

The flow computer is compatible with a wide range of flowmeter frequency outputs. Millivolt signals, reed switches, Namur proximity switches or pulse trains area selectable via its smart front-panel programming. To obtain accurate values of density and compressibility factors for the flow calculations, the AGA-8 Detail Characterization Method will be used.


  • The gas compressibility factor and density calculations are based on the AGA-8 equations.
  • The calculations are valid for the region:

-130°C < t < 400°C P < 280MPa -200°F < t < 760°F P < 40000psia FORMULAS Mflow = volumeflow•ρflow corrected flow = Mflow/ρ ref Heat flow = Mflow•Hm Where: Mflow = mass flow ρflow = density at flow conditions ρ ref= density at reference conditions Hm= mass gross heating value